--  @testpoint:opengauss关键字restrict(非保留)，作为函数名

--关键字不带引号-成功
drop function if exists restrict;
create function restrict(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
drop function restrict;
--关键字带双引号-成功
drop function if exists "restrict";
create function "restrict"(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
drop function "restrict";
--关键字带单引号-合理报错
drop function if exists 'restrict';
create function 'restrict'(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/
--关键字带反引号-合理报错
drop function if exists `restrict`;
create function `restrict`(i integer)
returns integer
as $$
begin
    return i+1;
end;
$$ language plpgsql;
/